Recommendations
Key Recommendations
If the patient has a confirmed proximal DVT, start anticoagulation (unless contraindicated).[12][26][27]
Base your choice of anticoagulant on the patient’s comorbidities and contraindications as well as taking account of local guidelines. Consult a haematologist if a patient has a contraindication to anticoagulation.
Apixaban or rivaroxaban are first-line if there are no special considerations; low molecular weight heparin followed by dabigatran or edoxaban or overlapped with warfarin is an alternative if apixaban or rivaroxaban are unsuitable.[12][26]
Be aware of special patient groups, including pregnant patients; those with active cancer, renal impairment, or hepatic impairment; and patients at extremes of body weight. These groups will need a tailored approach to anticoagulant therapy.[12] Check your local protocols and consider seeking advice from a haematologist, particularly if the patient has triple-positive antiphospholipid syndrome.
Give anticoagulation for at least 3 months.[12] Longer-term, or sometimes indefinite, anticoagulation may be needed for secondary prevention after weighing the individual patient’s risk of recurrence versus bleeding risk.[12]
If you suspect phlegmasia cerulea dolens (PCD), act quickly because PCD is a life- and limb-threatening emergency; do not wait for the results of investigations to start treatment.[26] Immediately start anticoagulation, refer the patient to a vascular surgeon, elevate the affected limb, and seek advice from critical care.
If the patient has a confirmed distal (calf) DVT, check your local protocol for advice on whether and how to start anticoagulation; guidelines vary in terms of their recommendations. In the UK, common practice is to start anticoagulation unless the patient has a high risk of bleeding or the DVT is not extensive (<5 cm).
Advise early mobilisation and consider compression stockings to manage acute symptoms.[26][27]
Most patients with DVT can be safely discharged and managed at home.[27]
Most patients with suspected or confirmed DVT can receive treatment at home, rather than in the hospital.[27] Outcomes are at least as good as those achieved with hospitalisation, and improved patient satisfaction.[103]
[ 
]
[Evidence C] However, arrange hospital admission if any of the following apply:
Suspected or confirmed concomitant pulmonary embolism (PE) requiring admission (e.g., haemodynamically unstable, intermediate-risk PE based on the Pulmonary Embolism Severity Index [PESI] score or the simplified Pulmonary Embolism Severity Index [sPESI] score).[12][104] See our topic Pulmonary embolism for more information on criteria for admission for a patient with concomitant PE
Highly symptomatic DVT (e.g., severe pain and oedema in the presence of acute DVT requiring inpatient analgesia), or phlegmasia cerulea dolens
The patient needs support with ongoing anticoagulation therapy that cannot be adequately arranged in the outpatient or emergency department setting
Co-existing comorbidity requiring hospital management
DVT that is best treated with intravenous unfractionated heparin.
In practice, most patients with risk factors for bleeding that require close observation (e.g., chronic liver disease with or without varices, recent or prior gastrointestinal bleeding, chronic renal stones with recurrent haematuria, bleeding disorder, malignancy, recent stroke, or prior intracranial haemorrhage) can be managed at home unless they are actively bleeding. Seek advice from a senior colleague if you are unsure.
If you suspect phlegmasia cerulea dolens (PCD), act quickly because PCD is a life- and limb-threatening emergency; do not wait for the results of investigations to start treatment.[26] Immediately:
Before starting interim therapeutic anticoagulation for suspected DVT, order baseline blood tests including full blood count, renal and hepatic function, prothrombin time (PT), and activated partial thromboplastin time (aPTT).[12][26]
However, do not wait for the results of these before starting anticoagulation.[12]
Review the results (and act on these if necessary) within 24 hours of starting anticoagulation.[12]
Practical tip
If D-dimer testing is required, always order this before giving anticoagulation; a false negative D-dimer result can occur if blood is drawn after the patient has been given anticoagulation.[26]
If possible, choose an interim anticoagulant that can be continued if DVT is confirmed.[12] See Confirmed proximal DVT: initiation phase of anticoagulation (up to 10 days following diagnosis) below for more information about anticoagulation.
Start interim therapeutic anticoagulation (as long as there are no contraindications) if:[12]
The patient is categorised as ‘DVT likely’ (Wells score ≥2) and the result of venous ultrasound is not available within 4 hours
The patient is categorised as ‘DVT unlikely’ (Wells score <2) and:
The D-dimer level has been taken but the result is not available within 4 hours
OR
The D-dimer result is positive, and a venous ultrasound has been arranged with the result available within 24 hours
You suspect DVT clinically in a pregnant patient.[27] Do not wait for the results of imaging.[27]
Stop interim therapeutic anticoagulation if venous ultrasound is negative.[12]
The initiation phase covers the period up to 10 days following diagnosis of DVT.[26]
Give anticoagulation (unless contraindicated) to all patients if they have a proximal DVT.[12][26][27] The National Health Institute for Health and Care Excellence (NICE) in the UK recommends that patients with proximal DVT of the leg should receive anticoagulation for at least 3 months.[12]
Note that a separate initiation phase may only be required if the patient is receiving warfarin, because warfarin requires a loading period. In UK practice, direct oral anticoagulants (DOACs) are more widely used than warfarin; therefore, the initiation and treatment phases are usually combined, spanning the period from diagnosis to 3 months.
The aim of the initiation phase is to stop the active prothrombotic state and to inhibit thrombus propagation and embolisation.
Anticoagulation is the mainstay of therapy for the treatment of DVT and can:
Prevent propagation/progression of the thrombus in the deep veins in the legs
Reduce the risk of pulmonary embolism
Reduce the risk of recurrent DVT.
Base your choice of anticoagulant on the patient’s comorbidities and contraindications as well as taking account of local guidelines.
Consult a haematologist if the patient has a contraindication to anticoagulation. See Patients with a contraindication to anticoagulation below.
More info: DOACs
The DOACs rivaroxaban, apixaban, edoxaban, and dabigatran are as effective as unfractionated heparin (UFH), low molecular weight heparin (LMWH), and warfarin for the treatment of DVT, and are generally recommended over warfarin, UFH, and LMWH outside of special populations.[12][110] No monitoring of coagulation profile is necessary, and bleeding complications are similar to those of warfarin, but there is a lower or similar incidence of major bleeding with pulmonary embolism. All have a longer half-life than UFH or LMWH and a shorter half-life than warfarin, and all have a rapid onset of action.
Unlike warfarin, DOACs do not interact with food. However, rivaroxaban at doses ≥15 mg/day should be given with the largest meal of the day (most often the evening meal) to maximise absorption.
DOACs do, however, have some drug-drug interactions. Notable drug interactions include: strong P-glycoprotein inducers and inhibitors (dabigatran and edoxaban); strong inhibitors or inducers of P-glycoprotein and CYP3A4 (apixaban and rivaroxaban).
Specific reversal agents for dabigatran (idarucizumab) and the oral factor Xa inhibitors apixaban and rivaroxaban (recombinant coagulation factor Xa [andexanet alfa]) have been approved in the UK. Note that andexanet alfa is only approved for life-threatening or uncontrolled gastrointestinal bleeding in England. Reversal of warfarin, in the setting of major or life-threatening bleeding, is recommended with vitamin K and prothrombin complex concentrates.[111]
Dabigatran and edoxaban require lead-in therapy with a parenteral anticoagulant such as UFH or LMWH for 5 to 10 days.
Rivaroxaban and apixaban are initiated at a higher initial dose (for 7-21 days) with no need for lead-in therapy with a parenteral anticoagulant.
Argatroban (a thrombin inhibitor) or danaparoid may be used if the patient has suspected or confirmed heparin-induced thrombocytopenia (HIT).[26] Bivalirudin, desirudin, and fondaparinux have also been suggested, but are not licensed for active HIT in the UK.[26] IHI: anticoagulant toolkit – reducing adverse drug events Opens in new window [
]
More info: Warfarin
Start warfarin within 24 hours of diagnosis and ensure overlap with parenteral anticoagulation for at least 5 days or until the international normalised ratio (INR) is ≥2 for at least 24 hours (whichever is longer).[12] Subsequent dosing of warfarin is based on the INR response to each dose. The therapeutic INR range is 2 to 3 (target 2.5, unless concomitantly being used for anticoagulation of mechanical heart valves).
Three strategies can be used to select the initial dose of warfarin: a clinical algorithm calculates the estimated stable and starting dose based on several patient characteristics; a genetic algorithm calculates the estimated stable and starting dose based on the results of genetic tests such as CYP450-2C9 genotype and VKOR-C1 haplotype, as well as clinical variables; a fixed-dose approach uses initiation nomograms based on starting doses of 5 mg/day or 10 mg/day.[112][113] [
]
Use of an individualised nomogram for selecting the initial warfarin dose, and for subsequent titrations, is likely to result in better outcomes than a fixed-dose initiation, and is preferred.[113][114] Tests are available that determine the genotype of the patient for cytochrome 2C9 variants and vitamin K epoxide reductase variants. However, overall, this information has not led to more rapid or safe anticoagulation compared with routine dosing. Genotyping is expensive and it takes several days to receive results.[115][116][117][118]
If available, take an individualised approach to warfarin initiation. Use an online tool to assist with warfarin initiation dosing that utilises clinical variables with or without the addition of genetic information. Warfarin dosing Opens in new window
More info: Unfractionated heparin, low molecular weight heparin, and fondaparinux
Unfractionated heparin (UFH) treatment is usually initiated with an intravenous weight-based loading bolus followed immediately by initiation of a weight-based continuous infusion. It also requires monitoring of activated partial thromboplastin time or heparin-calibrated anti-Xa activity, which is used to titrate dosing to the target range.
Low molecular weight heparin (LMWH) and fondaparinux are dosed subcutaneously, according to patient weight.
Platelet count is measured prior to, and regularly during, treatment with any heparin (e.g., UFH, LMWH) therapy because of the possibility of heparin-induced thrombocytopenia as a complication.
Confirmed proximal DVT
See Confirmed proximal DVT: special patient groups below if the patient is pregnant; has active cancer, renal impairment, or hepatic impairment; or is at extremes of body weight.
For all other patients with confirmed proximal DVT, start anticoagulation as soon as possible with apixaban or rivaroxaban (these are examples of DOACs); low molecular weight heparin (LMWH) is an alternative if these are unsuitable.[12][26]
Use argatroban (a thrombin inhibitor) or danaparoid if the patient has suspected or confirmed heparin-induced thrombocytopaenia (HIT).[26] Bivalirudin, desirudin, and fondaparinux have also been suggested as suitable options, but are not licensed for active HIT in the UK.[26] IHI: anticoagulant toolkit – reducing adverse drug events Opens in new window [
]
See the Complications section for more information.
If using rivaroxaban or apixaban, note that these drugs may be started without the need for lead-in therapy with a parenteral anticoagulant first.[12]
Acute-phase treatment consists of an increased dose of the oral anticoagulant over the first 3 weeks (for rivaroxaban), or over the first 7 days (for apixaban).[27]
If using LMWH, continue treatment for at least 5 days.[12]
If ongoing anticoagulation will be with edoxaban or dabigatran, note that at least 5 days of lead-in therapy with LMWH is required first
OR
If ongoing anticoagulation will be with warfarin, start warfarin within 24 hours of diagnosis and ensure overlap with LMWH for at least 5 days or until the international normalised ratio (INR) is ≥2 for at least 24 hours (whichever is longer).[12]
Practical tip
Never give a DOAC simultaneously with parenteral anticoagulation.
While warfarin is started at the same time as a parenteral anticoagulant and overlapped for at least 5 days or until the INR is ≥2 for at least 24 hours (whichever is longer), DOACs should never be overlapped or given at the same time as a parenteral anticoagulant.
Apixaban and rivaroxaban may be started without the need for lead-in therapy with a parenteral anticoagulant first.
However, dabigatran and edoxaban require at least 5 days lead-in therapy with a parenteral anticoagulant before starting treatment. The parenteral anticoagulant should be stopped before dabigatran or edoxaban are started.
Confirmed proximal DVT: special patient groups
Be aware of special patient groups, including pregnant patients; those with active cancer, renal impairment, or hepatic impairment; and patients at extremes of body weight. These groups will need a tailored approach to anticoagulant therapy.[12] Check your local protocols and consider seeking advice from a haematologist, particularly if the patient has triple-positive antiphospholipid syndrome (although this is unlikely to be known before anticoagulants are started).
Pregnancy
Use a weight-adjusted dose of LMWH in patients who are pregnant because LMWH does not cross the placenta.[26]
Do not routinely measure peak anti-Xa activity in patients who are pregnant (or in the postnatal period), except in patients who weigh <50 kg or ≥90 kg or those with renal impairment.[26]
Do not give DOACs or a vitamin K antagonist (VKA; e.g., warfarin) during pregnancy as they may cross the placenta.[26] Never give a DOAC if the patient is breasfeeding.[26] Warfarin appears to be safe to use in breastfeeding but in practice it may not be preferred (over LMWH) by the patient because it requires regular monitoring of INR.
Active cancer
Check local protocols for these patients. UK-based NICE recommends using a DOAC first-line.[12] Take into account the tumour site, the patient’s bleeding risk, and interactions with other drugs, including those being used to treat the cancer.[12] If a DOAC is unsuitable, NICE recommends using either:[12]
[ ]
LMWH alone
OR
LMWH overlapped with a VKA; warfarin is the most commonly used VKA in practice. Ensure overlap of the two drugs for at least 5 days or until the INR is ≥2 in two consecutive readings followed by a VKA on its own.
Note that warfarin is rarely used in UK practice for a patient with active cancer.
Renal impairment
Seek advice from a haematologist for these patients. NICE in the UK recommends the following approach based on estimated creatinine clearance (CrCl).[12]
For patients with CrCl 15-50 mL/minute, offer one of:
Apixaban (use caution if CrCl is 15-29 mL/minute)
Rivaroxaban (use caution if CrCl is 15-29 mL/minute)
LMWH or UFH, which can be overlapped with a VKA (warfarin is the most commonly used VKA in practice); overlap for at least 5 days or until the INR is at least 2.0 in 2 consecutive readings, followed by a VKA on its own) or used as lead-in therapy before starting edoxaban. LMWH or UFH can also be used as lead-in therapy before starting dabigatran if CrCl is ≥30 mL/minute.
For patients with CrCl <15 mL/minute offer one of:
LMWH or UFH, which can be overlapped with a VKA (warfarin is the most commonly used VKA in practice). Ensure overlap of the two drugs for at least 5 days or until the INR is ≥2 in two consecutive readings followed by a VKA on its own
LMWH alone
UFH alone.
Check your local drug formulary for any monitoring requirements or dose adjustments in renal impairment, particularly if CrCl is <15 mL/minute.[12]
Practical tip
Warfarin is safe to use in patients with renal impairment with no dose adjustments necessary. However, monitor the INR more carefully in these patients.
Hepatic impairment
Note that choice of anticoagulant for a patient with hepatic impairment depends on the underlying cause and severity of hepatic impairment.
In practice, patients may have acute, mild hepatic impairment (e.g., secondary to intercurrent illness) and, once their hepatic impairment has resolved, they may be treated with a DOAC.
DOACs are generally not recommended in patients with moderate to severe chronic liver disease (Child-Pugh class B or C).[27] However, apixaban may be used in selected patients, and LMWH or UFH are also options. In practice, overlap both LMWH and UFH with warfarin, unless cancer is present. Use warfarin with caution if the patient’s baseline INR is elevated; extended-duration LMWH may be preferred.[119]
NICE in the UK doesn’t give specific recommendations for patients with hepatic impairment.
Check your local drug formulary for any dose adjustments in hepatic impairment.
Extremes of body weight
Check your local protocols and consider seeking advice from a haematologist or a multdisciplinary team before choosing the most appropriate anticoagulant for these patients.[12]
In UK practice, a DOAC may be used if the patient weighs up to 120 kg, and rivaroxaban or apixaban may be used if the patient weighs >120 kg.[120]
However, NICE recommends using an anticoagulant with monitoring of therapeutic levels (e.g., warfarin) if the patient weighs <50 kg or >120 kg, and checking any required dose adjustments.[12]
Practical tip
Drug-drug interactions may increase the risk of bleeding in patients receiving anticoagulation, particularly when anticoagulation is combined with antiplatelet therapy.[121] In practice, aspirin is generally stopped while the patient is receiving anticoagulation, unless there is a strong indication to continue it. Seek advice if in doubt. Both the pharmacodynamic (e.g., non-steroidal anti-inflammatory drugs, selective serotonin-reuptake inhibitors) and pharmacokinetic (e.g., amiodarone, rifampicin) interactions should be thoroughly evaluated prior to initiation of anticoagulation. In particular, commonly overlooked interactions include those between a DOAC and phenytoin, carbamazepine, and HIV protease inhibitors.
Continue anticoagulation for a minimum of 3 months.[12][27] During this time, follow-up and re-evaluation are based on the patient’s level of risk for bleeding, comorbidities, and the anticoagulant selected.
In UK practice, because direct oral anticoagulants (DOACs) are more widely used than warfarin, the initiation and treatment phases are usually combined, spanning the period from diagnosis to 3 months. A separate initiation phase may only be required if the patient is receiving warfarin, because warfarin requires a loading period.
The aim of the treatment phase is to prevent new thrombus while the original clot is stabilised and intrinsic thrombolysis is under way.
DOACs
If the patient is taking dabigatran or edoxaban, continue the same dose started in the initiation phase for at least 3 months.[27]
However, if the patient’s renal function declines significantly, the DOAC should be discontinued.[27] In practice, switch to an alternative anticoagulant (unless the patient has a very low-risk DVT [e.g., small distal DVT]).
If the patient is taking apixaban or rivaroxaban, adjust the dose after the initiation phase (at 7 days for apixaban, and 21 days for rivaroxaban).[27]
Warfarin
Monitor the patient’s international normalised ratio (INR). The frequency of measurements depends on the stability of INR values.
In practice, measure INR every 3 to 4 days during initial dose titration if the patient is being managed as an outpatient, with the time between measurements progressively extending if values remain in range. However, if the patient is in hospital, consider measuring INR daily, particularly if they are acutely unwell.
Maintain a target range of 2 to 3 (target INR 2.5), unless anticoagulation is also being used for a separate indication that requires a higher target INR.[27]
Low molecular weight heparin (LMWH)
If extended LMWH is used, the dosing strategy is agent-specific; check your local protocol and seek advice from a pharmacist/haematologist if you are unsure.
Adjust the LMWH dose to any change in the patient’s weight or creatinine clearance.
Bear in mind that not all patients will need continued anticoagulation beyond 3 months. The aim of the extended phase is secondary prevention of new venous thromboembolism. See the Prevention section for other methods of secondary prevention aside from anticoagulation.
Duration
Discuss with a senior colleague whether to continue anticoagulation beyond 3 months if the patient has a first presentation of proximal DVT. This decision should assess the individual patient’s risk of recurrence of DVT versus bleeding risk, as well as considering whether the DVT was provoked or unprovoked.[12] Discuss the risks and benefits of long-term anticoagulation with the patient, and take their preferences into account.[12]
A provoked DVT is a DVT associated with a major transient risk factor that was present in the 3 months prior to the DVT.[12]
An unprovoked DVT is a DVT in a patient who had no pre-existing, major, transient, provoking risk factor in the prior 3 months.[12]
Major provoking risk factors include: major surgery; trauma; significant immobility (bedbound, unable to walk unaided, or likely to spend a substantial proportion of the day in bed or in a chair); pregnancy or puerperium; use of oral contraceptive/hormone replacement therapy.[12]
In general, anticoagulation can usually be stopped after 3 months (or 3-6 months for people with active cancer) if the DVT was provoked, as long as the major transient risk factor is no longer present and the clinical course has been uncomplicated.[12]
In the UK, some centres may continue anticoagulation beyond 3 months for patients with a minor transient risk factor (e.g., minor surgery).
Anticoagulation is usually continued for longer than 3 months if the DVT was unprovoked.[12]
In practice, patients with persisting risk factors (e.g., active cancer, autoimmune conditions such as systemic lupus erythematosus and inflammatory bowel disease) usually continue anticoagulation long-term, unless they had a major provoking risk factor (e.g., major surgery).
If the patient has active cancer, anticoagulation is continued for at least 6 months.[12] In practice, this will be for at least the duration of cancer treatment, or until remission is achieved.
Annually reassess the risks/benefits of continuing anticoagulation, as well as the patient's general health and treatment preferences, in all patients receiving extended treatment beyond 3 months.[12][60]
Choice of anticoagulant
In general, offer continued treatment with the anticoagulant used in the acute phase if it is well tolerated.[12]
If the patient has been started on a direct oral anticoagulant other than apixaban and this is not well tolerated, or the clinical situation or patient preference has changed, the National Institute for Health and Care Excellence in the UK recommends to consider switching to apixaban if the patient does not have renal impairment, active cancer, established triple-positive antiphospholipid syndrome, or extreme body weight (<50 kg or >120 kg).[12] However, in practice, many patients may prefer an alternative anticoagulant that can be taken as a once-daily regimen.
In patients taking apixaban who need ongoing anticoagulation for >6 months, consider a dose reduction.[122] In UK practice, if the patient is taking rivaroxaban in this scenario, a dose reduction may be considered if there is concern about the risk of bleeding.
In pregnant patients, continue low molecular weight heparin for the remainder of the pregnancy and for at least 6 weeks postnatally and until at least 3 months of treatment has been given in total.[123]
Consider aspirin if the patient declines or is unable to tolerate any form of oral anticoagulant.[12]
More info: Anticoagulation for unprovoked DVT
Many studies have attempted to identify subgroups of patients with unprovoked venous thromboembolism (VTE) who do not need to be treated indefinitely with oral anticoagulation. There is strong evidence that the risk of recurrent VTE is higher in the following patients: male sex; those with a diagnosis of a proximal DVT (versus isolated distal [calf] DVT); those with ultrasound evidence of residual clot; those who have an elevated D-dimer 1 month after stopping a 3- to 6-month course of oral anticoagulation; and those who had an unprovoked DVT.[27][124][125][126][127] Several risk assessment models have been developed for this purpose, including the DASH score, the Vienna Prediction Model, and the 'Men Continue and HER-DOO2' model.[128] The latter model identifies a subset of women with low risk for recurrent VTE after an initial unprovoked event, and a prospective validation study of this model has been published.[129] However, these models are not widely used in practice.
If a whole-leg ultrasound confirms distal (calf) DVT, check your local protocol for advice on whether and how to start anticoagulation; guidelines vary in terms of their recommendations.
In the UK, common practice is to:
Start anticoagulation unless the patient has a high risk of bleeding or the DVT is not extensive (<5 cm)
Seek advice from a haematologist if the patient has a high bleeding risk or the DVT is not extensive.
The European Society for Vascular Surgery recommends considering anticoagulation based on the patient’s symptoms, risk factors for extension, and bleeding risk.[26]
Note that the National Institute for Health and Care Excellence in the UK does not give recommendations for distal (calf) DVT.[12]
If anticoagulation is suitable, use the same regimens as for proximal DVT.[130] Take into account the patient’s comorbidities, contraindications, and your local guidelines. See Confirmed proximal DVT: initiation phase of anticoagulation (up to 10 days following diagnosis) above for information about starting anticoagulation.
If anticoagulation is not suitable, or contraindicated, check your local protocol to determine further management. The European Society for Vascular Surgery recommends arranging clinical reassessment and repeat whole-leg ultrasound after 1 week.[26]
Risk factors for extension include:[130]
Positive D-dimer
Extensive DVT (e.g., >5 cm long)
DVT involving multiple veins
DVT >7 mm in maximum diameter (however, in practice this measurement is not routinely reported)
DVT close to the proximal veins
Absence of any reversible provoking factor
Active cancer
Past history of venous thromboembolism
Patient being managed in hospital.
Consider using compression stockings to manage leg symptoms such as pain, oedema, and residual venous obstruction.[12][26]
The National Institute for Health and Care Excellence in the UK does not recommend using compression stockings to prevent post-thrombotic syndrome.[12] This is debated in the literature; consult your local protocol.[131] [
]
Explain to the patient how to use the stockings, how long they should be worn, and when they should be replaced.[12]
Advise early mobilisation and walking exercise to relieve symptoms of acute DVT.[27] Some sources suggest that this light physical activity may also help to reduce the risk of post-thrombotic syndrome.[132][133][134][135]
Consult a haematologist if the patient has a contraindication to anticoagulation.
Many patients with relative contraindications will still be able to have a different choice or altered dose of anticoagulation, but a specialist opinion is needed to weigh up the benefit-risk balance.
Absolute contraindications are rare but include:[136]
Active bleeding
Recent intracranial haemorrhage
Recent, planned, or emergent surgery or procedure with high bleeding risk
Platelet count <50,000/uL
Severe bleeding diathesis.
Relative contraindications include:[136]
Recurrent but inactive gastrointestinal bleeding
Intracranial or spinal tumour
Recent, planned, or emergent surgery or procedure with intermediate bleeding risk
Major trauma including cardiopulmonary resuscitation
Aortic dissection.
Remember, too, that each anticoagulant may have its own specific relative and absolute contraindications (e.g., heparin is contraindicated in patients with a history of heparin-induced thrombocytopenia) and these should be checked before starting treatment.
Practical tip
Peptic ulcer disease with no history of bleeding or faecal occult blood is not a contraindication to anticoagulation.[136]
Anticoagulation is safe in most trauma and neurosurgical patients after the first or second postoperative week and in most stroke patients without haemorrhage.[136]
Patients with spinal cord injury without haematomyelia may still be considered for anticoagulation.[136]
Consider a retrievable inferior vena cava (IVC) filter for any patient with confirmed proximal DVT who is deemed unsuitable for anticoagulation after discussion with a haematologist.[12][26][27] The aim of an IVC filter is to prevent embolisation to pulmonary embolism.[26]
Presence of an IVC filter is associated with a doubling of the long-term risk of recurrent lower-extremity DVT.
If the contraindication to anticoagulation has resolved, assess the patient for initiation of anticoagulation and removal of the IVC filter.[27]
Practical tip
Always document the plan for IVC filter removal at the time it is inserted. Forgotten IVC filters can lead to significant long-term complications.
Seek advice from haematology for any patient who has a recurrent venous thromboembolism (VTE) despite adequate anticoagulation treatment. Recurrent VTE is unusual among patients receiving therapeutic-dose anticoagulant therapy, except in those with active cancer (7% to 9% on-therapy recurrence with low‐molecular‐weight heparin).[13][137][138]
Check adherence to anticoagulation treatment.[12]
Address other sources of hypercoagulability (e.g., underlying malignancy).[12]
Consider other reasons for reduced efficacy of anticoagulation (e.g., rivaroxaban not being taken with food).[139]
In the absence of any of the above issues, options include:[12]
Increasing the dose of anticoagulant
Changing to a different anticoagulant with a different mode of action.
Patients with recurrent VTE despite treatment with adequate anticoagulation can be considered for an inferior vena cava filter.[12]
Note that these recommendations are based on the National Institute for Health and Care Excellence guideline in the UK, which covers patients with proximal DVT only. In UK practice, some experts may apply these recommendations equally to patients with distal (calf) DVT in the absence of recommendations from guidelines. Seek advice from a specialist if needed.
Use of this content is subject to our disclaimer